Schmoozer (noun)

1. A person who is skilled in ingratiating themselves with others, especially for personal gain.
2. A person who is adept at making casual conversation in a friendly and ingratiating manner.

Origin:

It is believed to have originated from yiddish word "shmuesn" meaning to chat or talk, it was popularized by al capp"s li"l abner comic strip in the 1940s.

Examples:

1. He was a master schmoozer and knew how to charm his way into any situation.
2. The schmoozer was always looking for ways to make connections and gain favors.
3. He was a notorious schmoozer who would talk to anyone in order to get ahead.
4. A party is not complete without a few good schmoozers.
5. The schmoozer made a good impression on the new client by chatting them up and showing genuine interest in their business.